Plate-printing press



(No Model.) 2 Sheets-Sheet 1.

W. G. DEMAIN.

PLATE PRINTING PRESS.

No. 269,393. Patented Dec.19,1882.

Witnesses: .Eavenior:

(No Model.) 2 Sheets-Sheet 2. W. O. DEMAIN.

PLATE PRINTING PRESS.

110.269.5593. Patented Dec. 19, 1882.

UNITED STATES,

PATENT FFICE. V

\VILLIAM U. DEMAIN, OF MEDFORD, MASSACHUSETTS.

PLATE-PRINTING PRESS.

SPECIFICATION forming part of Letters Patent No. 269,393, dated December19, 1882.

- Application filed May 24, 1882. no model.)

To all whom it may concern Be it known that I, WILLIAM CHARLES DE- MAIN,of Medford, in the county of Middlesex and State of Massachusetts, haveinvented certain new and useful Improvements in Plate- Printing Presses,of which the following, taken in connection with theaccompanyingdrawings, is a specification.

My invention relates especially to improvements in the device forconnecting the impression-cylinder with the plate-carrying carriage orplank to cause them to move in unison, and to an improved adjustableclamp for securing the lower end of the blanket, which will be bestunderstood by reference to the following description of the drawings, inwhich Figure l is a vertical section of a plateprinting press embodyingmy present invention, the cutting plane heingjust inside of one of theside frames. Fig. 2 is a horizontal section on line a: w on Fig. 1.Fig.3 is a section of one end of the impression-cylinder and adjustablearm secured thereto. Fig. 4 is an elevation of the clamp for holding theend of the blanket, and Fig.5 is a section of the same on line 3 y on Fi4.

A A are the two side frames ofthe machine, connected together bysuitabletie-rods, a a, and having mounted in suitable bearings there in thecylinder B, rolls 0 O, and impressioncylinderD.

The bed-supporting plank E is mounted upon the cylinder B and rolls 0 O,and carries near its frontend the bed F, to which is socured the gage 0,against which the front edge of the plate (Z is placed, as shown. Afterthe impression is given the plank E is moved toward the front of themachine by the expansion of the springs g g, surrounding the rods- 6 e,which are secured at their front ends to the plank E.

H is an arm pivoted at its rear end to the adjustable bar I, secured tothe plank E by a bolt, a, passing through the slot n in said bar. Thearm H is notched at its forward end, and is supported in a horizontalposition, or nearly so, by the spring J, as shown.

The press as thus described forms no part of my present invention, as itis substantiallythe same in construction and operation as the one shownand described in Letters Patent No.

256,413, granted to me as the assignee ofJames Tregurtha, April ll.1882.

I will now describe the devices which constitute my present invention.

Secured upon one end of the roll D is the adjustable radius-arm G,provided with a ring portion, which surrounds the roll D, said ringportion having ajoint, 1), upon one side thereof. Two ears-0ne upon eachside of thejoint b-are connected tOgGtlJGI' by the bolt f, by whichmeans the joint I) is closed, or partly closed, to compress the ringfirmly around the roll D.

From the inner circumference of the ring portion of the arm G projecttwo flanges or ribs, h h, which fit into grooves turned in the roll Dnear its end, as shown in Fig. 3, in order t6 prevent the arm G fromslipping off the roll D when adjusting said ring about the axis of theroll. in securing the arm G in position the boltfis first removed. Thering is then sprung open until it will slip over the portion 1 betweenthe grooves before mentioned, and when the ring comes in contact withthe shoulderj on the roll D, the boltf may be inserted and screwed up,thus clamping the ring firmly in position. The-depth of the grooves inthe roll D, which receive the flanges h h, is but slight; but it issufticient to prevent the arm G from slipping eudwise of said roll. Iprefer to make the arm G of cast-steel to obviate the danger of breakagewhen springing the ring into position.

in the outer end of the arm G is secured the stud Z, which, at theproper time in the rotation of the roll D, engages with the notchedforward end of the arm H to carry the plank E and bed F into position togive the impression, as described in the Letters Patent before cited.For the purpose of adjusting the various parts, graduated scales are cutor affixed to the plank E, the bed F, and-the roll D, the same asdescribed in the above-mentioned Letters Patent.

The second portion of my invention pertains to the adjustable clamp Lfor securing the lower end of the blanket to the plank E. This clamp ismade in two parts, 0 and p, thelower part, 1), having arearwardly-projecting horizontal foot, q, provided with alip, 1", whichextends longitudinally thereof, and is fitted to a groove, n, in theupper side of the plank E, said foot q being also provided with a slot,1", by means of which and the thumb-screw k the clamp L may be firmlysecured to and adjusted upon the plank E. Two studs, 8 s, are screwedinto the opposite ends of the piecep, and, passing through holes in theopposite ends of the upper portion, 0, are provided at their upper endswith thumb-nuts t t, by means of which the two portions-of the clamp Lare compressed upon the end of the blanket. Two springs, s s, surroundthe studs 8 s between the upper and lower portions of the clamp L, andact by their expansive force to open said clamp when the thumb-nuts t tare unscrewed. Extending along the lower edge of the piece 0 are tworibs, 26 u, and upon the upper edge ot'the piece 29 is a single rib, 1),which tits between the ribs u u when the clamp is closed, as shown inFig. 5, the purpose of said ribs being to enable the clamp L to hold theblanket more securely.

hat I claim as new, and desire to secure by Letters Patent of the UnitedStates, is-

one side, and a screw-bolt extending across said cut, and adapted toclamp the arm to the D-cylinder in any desired position.

2. The clamp L, provided with the slotted foot (1, in combination withthe plank E and the clamping-bolt or thumb-screw 7;, all arranged andadapted to operate substantially as described.

Executed at Boston, Massachusetts, this 22d day of May, A. D. 1852.

WILLIAM CHARLES DEMAIN.

Witnesses:

E. A. HEMMENWAY, WALTER E. LOMBARD.

